[Bug libfortran/78549] Very slow formatted internal file output

[manfred99 at gmx dot ch]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78549

--- Comment #29 from Manfred Schwarb <manfred99 at gmx dot ch> ---
Here are the results from my test case from PR82938 
(without the "print*,f" statement, which consumes ~1s):

  1.1s for GNU Fortran (GCC) 8.0.0 20170828 (experimental) [trunk revision
251373]
  3.3s for GNU Fortran (GCC) 8.0.0 20170829 (experimental) [trunk revision
251395]
  1.3s for GNU Fortran (GCC) 8.0.0 20171123 (experimental) [trunk revision
255090]
  0.4s for version with Fortran wrapper of C function strtof()

So, with Jerry's patch gfortran is now only a little slower than before
the DTIO patches, so still some minor regression for internal read. 

But there is still some large gap compared to the C routine version...